Question

Give reasons:
1. A bullet fired against a glass window pane makes a whole in it without cracking it
2. When a tree is shaken ,its fruits and leaves fall down

Answer 1

$$\begin{gathered} \left(\mathrm{a}\right)\mathrm{When}\mathrm{the}\mathrm{bullet}\mathrm{strickes}\mathrm{the}\mathrm{glass},\mathrm{the}\mathrm{part}\mathrm{of}\mathrm{the}\mathrm{glass}\mathrm{which}\mathrm{comes}\mathrm{in}\mathrm{contact}\mathrm{with}\mathrm{the} \\ \mathrm{bullet}\mathrm{immediately}\mathrm{shares}\mathrm{the}\mathrm{large}\mathrm{velocity}\mathrm{of}\mathrm{the}\mathrm{bullet}\mathrm{while}\mathrm{the}\mathrm{remaining}\mathrm{part}\mathrm{of}\mathrm{the} \\ \mathrm{glass}\mathrm{due}\mathrm{to}\mathrm{inertia}\mathrm{at}\mathrm{rest},\mathrm{remains}\mathrm{at}\mathrm{rest}\mathrm{and}\mathrm{is}\mathrm{therefore}\mathrm{not}\mathrm{smashed}. \end{gathered}$$

(b) When we shake the tree, leaves and fruit fall down. The branch of the tree comes in motion but the fruit and leaves tend to remain at rest. Therefore, it get detached.